Generally, a ground effect machine is a generic name of vehicles which aviate by utilizing a lift of an air cushion confined in between the airframe bottom surface and the ground or water surface, or ground effects of wings. Popular names of these vehicles are, for instance, a Hovercraft (brand name) or an air cushion vehicle. The ground effect machines are classified roughly into two; one group includes a peripheral jet type, a pressure chamber type, and an air lubricating type which utilize a dynamic lift; another group includes ram wings and ground effect wings which utilize a dynamic lift. The peripheral jet type is a typical machine arranged in such a way that the air is jetted downwards from a peripheral part of the bottom surface of the airframe. The airframe is equipped with a flexible skirt to travel on unlevelled ground or waves.
A typical arrangement, of an existing small-sized air cushion vehicle among the ground effect machines, has a single propeller mounted on the airframe and rotated by an engine, approximately one-third of the quantity of air generated by the propeller being employed for levitating the airframe, and the remaining two-thirds of air being used for propelling the airframe.
When a battery serves as the power supply for an electromotive toy in the form of a small-sized air cushion vehicle, there is a limit to the output of the motor mounted thereon. It is difficult to obtain propulsion and also levitate the airframe by a single propeller. Where fans are separately provided for both buoyancy and propulsion, a propeller employed as a levitating fan can be part of a general air blowing means. However, the propeller has a quite poor efficiency in terms of increasing air pressure. The air flows back from the propeller, unless a motor capable of rotating at high speed and having a large torque is employed, with the result insufficient pressure is obtained to levitate the airframe. Even if the airframe is levitated by using a motor having large torque, the resultant toy is unsatisfactory in terms of the life span of the battery. The propeller has to be rotated at a high velocity, which in turn causes loud noises. Also, with a mechanism for manipulating an inclined angle of a rudder placed at the rear of the airframe for changing the propulsive direction, the responsiveness thereof in a toy is poor, thereby creating difficulty of handling.
Thus, the prior art does not provide an air cushion vehicle toy capable of obtaining both sufficient buoyancy and propulsion when using a simple battery as the power supply and freely controlling navigation with a high degree of dependability.